Having excellent transparency, an acrylic resin is used for a front panel of various displays including CRT and a liquid crystal TV, and also widely used as industrial materials or constructional materials. However, the acrylic resin does not necessarily have sufficient impact strength.
As a method of improving impact resistant of an acrylic resin, there is a method of adding rubber particles of multilayer structure polymer containing an elastomer layer to an acrylic resin and cast-polymerizing it (see, Patent Document 1). However, when the rubber particles are added to an acrylic resin, heat resistance or elasticity of the acrylic resin tends to be lowered.
There is also a method of dissolving an ethylene-vinyl acetate copolymer in methyl methacrylate and cast-polymerizing it (see, Patent Documents 2 to 4). However, the ethylene-vinyl acetate copolymer is problematic in that the side chains of the copolymer are decomposed by heat or UV rays to generate easily acetic acid.
There is also a method of co-polymerizing a copolymer of vinyl acetate and ethylene, or a copolymer of (meth)acrylic acid alkyl ester and ethylene with methyl methacrylate (see, Patent Document 5). However, as the addition amount of the copolymer of vinyl acetate and ethylene, or the copolymer of (meth)acrylic acid alkyl ester and ethylene is large, cost for producing an acrylic resin is high and transparency of an acrylic resin sheet tends to be lowered.